[PATCH 1/2] ARM: shmobile: sdhi: pass DMA filter from platform code
Arnd Bergmann
arnd at arndb.de
Fri Jun 7 08:52:28 EDT 2013
On Friday 07 June 2013 12:25:11 Guennadi Liakhovetski wrote:
> > /* SDHI0 */
> > static struct sh_mobile_sdhi_info sdhi0_info = {
> > +#ifdef CONFIG_SH_DMAE_BASE
>
> Right, that's the problem, I think. Don't think we want these #ifdefs in
> all shdma users - under arch/arm and arch/sh. That's why I think we need
> my fix in the first place to fix the compile breakage. After that we can
> think about improving DMA slave driver decoupling from specific DMAC
> drivers - if at all needed.
>
> > .dma_slave_tx = SHDMA_SLAVE_SDHI0_TX,
> > .dma_slave_rx = SHDMA_SLAVE_SDHI0_RX,
> > + .dma_filter = shdma_chan_filter,
> > +#endif
Well, the problem is that you check the value of dma_slave_rx/tx in order
to find out whether you should do DMA in the driver. If the filter
function is NULL but the values are positive, I think the driver won't
actually fall back to PIO mode but just fail.
Arnd
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